1Department of Pharmaceutical Chemistry and Drug Quality Control, Faculty of Pharmacy, Tishreen University, Lattakia, Syria
2Department of Applied Chemistry, Faculty of Science, Damascus University, Damascus, Syria
A new simple and rapid spectrophotometric method for determination the accurate amount of vitamin C containedin pharmaceutical samples has been developed. The ferric chloride is reduced by vitamin C and then reacts with potassium ferricyanide to create a dark blue solution of Prussian blue. The resulted color was observant at the absorption wavelength of 697nm. Optimum reaction conditions of Ferric chloride, Potassium Ferricyanide concentrations, reaction time, temperature and pH where investigated. Influence of potential interfering substances were also examined.Analyzes of commercial pharmaceutical samples showed good correlation with the valuesgiven by the manufacturers and the results obtained by a titration method with Iodine. The apparent molar absorptivity value is found to be 3.25 × 103. The results of analysis have been validated statistically, with good correlation coefficient (0.999). The proposed method has better LOD and LOQ values than many methods used to determine vitamin C in pharmaceutical forms.
Vitamin C, Prussian blue, Spectrophotometric method, Validation, Molar absorptivity
